Focus Speedo Problem

[chrisrigby]

OK, here is the issue.

Ford Focus 1.8TDi on a 53 plate in the UK (2003 model). battery was on the way out, so replaced. Just after that the speedo stopped working. Assumed the VSS, so replaced it, but problem still there. The weird thing is, the speedo works fine if the outside temperature is above circa 20 degrees, but does not work if the temperature is below this. When the temperature is below this it works sometimes, but mostly not. When the speedo is not working the car does idle higher between gear changes, though I assume this is because the cluster is not getting any speed information. Returns to normal when the speedo starts working again. Also, as I drive along, if I switch off the ignition and then switch it back on again, the speedo starts to work, but very erratically.

Bad earth maybe?

Car also recently had a new cluster, so assume that not to be the problem.

I am pretty technically minded, but not a trained mechanic, so please keep replies fairly simple.

Any advice very much appreciated as I refuse to be beaten and think the whole outside temperature issue must be a big clue to someone out there with good technical knowledge.

Thanks

[mjt]

Our Focus suffered from intermittent speedo failure. The speedo would just suddenly drop to zero and the odometer stop working. Turning off the ignition would almost always cure it. The VSS and cluster were both changed (under dealer warranty) but that didn't cure it. Eventually it was found that the loom from the VSS was chafed where it was touching the gear linkage. That was repaired and it hasn't failed since (over 2 years ago).

I'm not saying that's your problem but it's worth checking.

[Andy 1965]

Did you replace the battery with a silver calcium one?

[chrisrigby]

Replaced with a Bosch S3 100 (70ah).

[jeebowhite]

if its silver calcium you should be OK, but if you have a bog basic lead, it doesnt work with the smart charge...

You can try taking the cluster out and giving a blast with WD40, this has been known to cure many a dodgy speedo (there was an issue with the MK1.5 where there was a known cluster failure).

[Stoney871]

There are three common problems with the focus speedos.

First theVSS fails, second the VSS wires get melted or damaged, third the speedo cluster is very sensitive to condensation.

WD40 or any water displacing spray onto the contacts/cluster board should help for a while.

I'm sure there was a recall for that problem.

[jeebowhite]

Unfortunately not covered as a full cost from Ford now, they do offer clusters at 50% or so as a "good will gesture"...

[chrisrigby]

Thanks for all the responses so far, but the main element that seems to determine if the speedo works is the outside temperature. When it's warm it works perfectly, when it's cold it does not. Rain does not effect it. It has had a new VSS and a new instrument cluster. Maybe there is an auto electrician out there who has come across this problem before.

Also, any Ford people who may be able to confirm whether there is a chance I have had a dodgy cluster fitted. Has anyone come across this?

Thanks again to all that have responded so far. I refuse to be beaten on this one.

[Hoozyerdaddy]

My speedo kept failing and the performance dipped too, I looked at all the possible options and decided I would fix it when I had the spare cash to do so, then, one day while it was raining heavily my engine management light came on and a friend of mine told me to remove the battery for five minutes to reset all the sensors, since I did that the speedo has not faltered once and nor has the performance. I would recommend trying this before anything else.

[jeebowhite]

Certainly an easy and simple fix to try! cant hurt! Keep an eye on it though Jay, I do wonder if its a long term fix or a short term forget...